Intaglio offset lithographic plate and process of making same



O. KOHN Dec. 17, 1929.

INTAGLIO OFF-SET LIKTHOGRAPHIC PLATE AND PROCESS OF MAKING SAME Filed Jan. 25, 1928 Patented Dec. 17, 1929 vmural) STATE-s PATENT OFFICE OSCAR KOEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO AQUATONE CORPORATION, A COR- IORATION OF DELAWARE INTAGLIO OFFSET LITHOGRAPHIC PLATE AND PROCESS OF MAKING SAME Application filed January 25, 1928. Serial No. 249,427.

My invention relates broadly to printing devices and more particularly to offset-lithography. f U

A particular object of the invention 1s to 5 provide an improved intaglio plate whereby re roductions can be made 'in one or more co ors, of line or pencil drawings, of type matter, and in half-tone photographs, wash drawings or other copy which is photographed through a half-tone screen or a mezzotint, etc.

Another articular object of the invention is to provi e an improved method for producing intaglio plates of.the character described.

One form of the invention is practiced by iirst producing a plate which has the printing surfaces in relief and is typical of those commonly employed to print half-tones by offset-lithography, and then platingtherelief plate With some substance, preferably nickel,-

in such manner that it becomes an intaglio plate.

' Many other objects and advantages 0f the construction herein shown and described Will be obvious to those skilled in the art from the 'disclosure herein given.

To this end my invention consists in the novel method and the novel construction, arrangement and combination of parts herein shown and described, and more particularly pointed out in the claims.

In the drawings, wherein like reference characters indicate like or corresponding a5 parts:

Fig. 1 is an elevation of an intaglio plate embodying my invention;

Fig. 2 is a greatly enlarged section taken on line 2-2 of Fig. 1;

Fig. 8 is a transverse section taken through a plate which is adapted to be used in the production of an intaglio plate embodying my invention;

Fig. 4 is a transverse section taken through the plate shown in Fig. 3, the plate being coated and having a negative superimposed upon said coating; and

lfig. 5 is a greatly enlarged fragmentary section taken through the plate shown in Figs. 3 and 4 after the platehas been treated so that'it has become a relief plate for printing half-tones by offset-lithography.

Referring for the present to Figs. 1 andv 2 wherein I have shown an intaglio plate which embodies my invention and is adapted to print half-tones by offset-lithography, the reference character 10 designates the improved device as a whole and the reference character 11 designates a plate or sheet of the particles 15 and therefore, permits the plate to be used for intaglio printing.

The coating 16 preferably consists of nickel although I contemplate using copper, mercury, chromium and zinc, or other metal for this purpose. It should be understood, however, that I am limited to the use of nickel, or any other metal, for this purpose only to the extent indicated in the appended claims.

It may be mentioned that the outer surface of the coating 16 is preferably grained or stippled similarly to the surface 13 as the coating 16 is relatively thin and is preferably applied to the stippled surface 13 in such manner that the stippling or graining on the surface 13 is duplicated on the outer surface of the coating 16.

lli/'hen an impression or reproduction is to be made from the intaglio plate 10, the stippled or grained surface of the coating 16 is preferably moistened with water, or the equivalent, and then an inked roller, or the equivalent, is applied to the plate in such manner that the exposed surfaces of the dot printing particles 15 are inked. An impression is then made from the plate upon a rubber blanket which is then used to print the reproduction upon a sheet of paper, or the equivalent.

In Figs. 3, 4 and 5, I have illustrated the 55 coating. The nickel is preferably provided manner in which I practice my improved method to produce the intaglio plate 10. Fig. 3 represents the aboveementioned plate 11 which ispreferably provided with the stippled or grained surface 13. As shown in Fig. 4, a coating 15a is preferably applied to the stippled sur ace 13, the coacting 15a preferably comprising albumen mixed with ammonium bichromate, or the equivalent. Siiperimposed upon the coating 15a is aphotographic negative 20, the arrangement being such that when the removable plate 11, coating 15a and negative 20 are exposed to the light, certain portions of the coating 15a are hardened to provide the aforementioned dot printing particles 15. This process is well known to those skilled inthe art and it is not necessary to give a detailed description thereof. However, it may be mentioned that after the negative has been removed from the coating 15a, ink is preferably applied to the coating and the unhardened portions of the coating are preferably wiped from the plate so that a plurality of relatively hard dot printing particles 15 remain upon the plate, the top surface of each particle 15 beine'- inked. Of course, it is understood thatin this instance, it is assumed' that the negative 20 has been obtained by photographing some object, drawing or the/equivalent, through a screen. It Ishould also be understood that a-mezzotint may be employed in place of the screen and that line or pencil drawings may be reproduced without photographing them through a screen.

After the relatively soft portions of the coating 15L have been removed from the plate 11, the stippled surface 13 of the plate `11 is preferably etched by subjecting it to some suitable acid in a manner well known to those skilled in the art. After the surface 13 has been etched in this manner, the plate 11 together with the dot printing particles 15 formed thereon provides a relief plate of the type commonly employed to print half-tones by offset-lithography.

In the next step of my improved method, l preferably plate the stippled surface 13 with some suitable substance. rlhis substance is preferably nickel although other substances may be used. rlhe nickel does not adhere to the inked surface of the dot printing particles 15 an d the thickness thereof is such that the printing surfaces of the particles 15 are disposed below the outer surface of the nickel to the stippled or grained surface 13 bv electroplating. Ubviously, Yan intaglio plate is provided and it is readily understood that the outer surface af the nickel coating 16A will have reproduced therein the graining or sti pling provided upon the surface 13 of t e plate 11. The construction of the completed intaglio plate is illustrated in Figs. 1 and 2 and described above. e

Having thus described my invention, it is obvious that various immaterial modications may be made in the saine without departing from the spirit of my invention; hence I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described, or uses mentioned.

lVhat I claim as new and desire to secure by Letters Patent is:

1. An intaglio plate for printing by off-set lithography, said plate including a grained sheet having printing surfaces thereon and a raised 'coating on said sheet bet-Ween said printing surfaces and higher than the same, said coating having a surface capable of retaining dampness and repelling ink whereby the raised coating prevents the spreading of Yink and confines the intended printing particles to their predetermined dimensions.

2. An intaglio plate for printing by off-set lithography, said plate comprising a grained sheet provided with printing surfaces and a lraised coating on said sheet between the printing surfaces and projecting thereabove, said coating having a hydrophilic surface having the capability of retaining dampness and the said coating prevent-ing the spreading of ink and confining the intended printing particles to theirv predetermined dimensions.

3. An intaglio plate for printing by off-set lithography, said plate comprising a grained sheethaving printing surfaces thereon and a raised coating on said sheet extending above the printing surfaces, said coating having al grained surface to thereby render it capa le of' retaining water dampness, and the said coating preventing the spreading of ink and confining the intended` printing particles to their predetermined dimensions.

4t. An intaglio plate for printing by ofi-set lithography, said plate comprising a grained sheet having printing surfaces thereon and a coating on said sheet between the printing surfaces and extending above the same, said coating having the characteristics of repelling ink and of retaining dampness and p reventing the spreading of ink and confining the intended printing particles to their predetermied dimensions.

5. An intaglio plate for printing by off-set lithography, said plate comprising a grained sheet having printing surfaces provided thereby, and a coating on said sheet between the printing surfaces and of greater depth thereof,l said coating com rising metal having the characteristics o repelling ink and being stippled to retain dampness and preventing the spreading of ink and confining the printing particles to their predetermined dimensions.

6. An intaglio plate for printing by off-set lithography, said plate comprising a grained iexible sheet having printing surfaces associated therewith and a coating on said sheet particles to their predetermineddimensions.

'i'. An intaglio plate for printing by off-set lithography, said plate comprising a grained zinc sheet having printing surfaces thereon, a nickel coating on said sheet between the printing surfaces and of a greater height `than the printing surfaces, said nickel coating being grained to render it hydrophile to thereby retain dampness and repel ink, the raised nickel coating preventing the spreading of ink and confining the intended printing particles to their predetermined dimensions. Y

8. in intaglio plate for printing by olf-set lithography, said plate comprising a flexible sheet having a substantially continuously grained upper surface and provided with a printing area thereon, a coating on said sheet between the printing surfaces of a greater depth than the printing surface, said coating having a grained surface corresponding substantially to the grained surface of the flexible sheet whereby to render it hydrophilic to retain dampness, the raised coating preventing the spreading of ink and confining the intended printing particles to their predetermined dimensions.

9. An intaglio plate for printing by off-set *lithography, said plate comprising a zinc sheet having a substantially continuously v *grained surface and being provided with a v- 'photographic printing area and a coating on said zinc sheet comprising nickel positioned between vthe printing area and extending thereabove, said nickel coating being grained at its-upper surface to render it hydrophilic to retain dampness and said coating preventing the spreading of ink and confining the intended printing particles to their predetermined dimensions.

lO. An intaglio plate for printing by oil'- set lithography, said plate having a grained sheet provided with printing surfaces and a coating on said sheet between the printing surfaces and of greater depth than the printing surfaces, said coating having a grained surface whereby to render it capableof retaining water dampness, the coating preventing the spreading of ink and confining the intended rinting particles to their predetermined imensions.

l1. An intaglio plate for printing .by 0E- set lithography, said plate. comprising a grained sheet having printing surfaces associated therewith and means on said sheet between said surfaces and yof a greater height than said surfaces, said means comprising hydrophile metal capable of retaining water vdampness and of repelling ink whereby the image of ink placed upon the printing surface will form an affinity for ink and the said means extending above the printing surfaces preventing the spreading of ink and confining the intended printing particles to their predetermined dimensions.

l2. An intaglio plate for printing by olf- `set lithography, said plate comprising. a

grained sheet with printing surfaces'thereon and a coating on said sheet between said surfaces and of greater depth than the surfaces, ink particles adhering to said sheet and providing printing surfaces thereon, said coating having a surface capable of retaining water dampness and of repelling ink whereby the image of ink placed upon the printing surface will form an affinity for ink and the coating extending above the printing surfaces will repel ink.

13. .dn intaglio plate for printing by offset lithography, said plate comprising a grained sheet having printing surfaces associated therewith with ink particles adhering thereto and a coating on said sheet positioned between said printing surfaces and ink particles thereon and of a greater height than the same, said coating having a rough, irregular surface tol retain water dainpness and repel ink, the coating preventing the spreading of the inl: particles and thereby confining the intended printing particles to their predetermined dimensions.

14. rlhe herein described method of making intaglio lates for printing by off-set lithography, t e steps which comprise producing a plate having printing surfaces in relief, applying a coating of greater height than the printing surfaces to said plate to render it intaglio, said coating having an irregular surface to retain water dampness and preventing spreading of ink and confining the intended printing area to its substantially predetermined dimensions.

15. The method of making an intaglio plate for printing by odset lithography which comprises, the steps of producing a plate having printing surfaces in relief, in applying a coating to said plate, said coating having a grained surface to render it capable of retaining moisture, maintaining the depth of the coating to an extent greater than that of the printing surfaces whereby the coating prevents the spreading of ink on the printing surfaces and confines the intended printing area to its predetermined dimensions.

16. The method of producing an intaglio plate for printing by olf-set lithography comprisin the steps of producing a plate having printing surfaces in relief and applying an ink repellent coating to said plate of a depth greater than theprinting surfaces to render it intaglio.

17. The method of producing an intaglio plate for printing by olf-set lithography, which method comprises producing a plate having printing surfaces in relief and applying a coating to said plate of a height greater than the printing surfaces to render 1t 1ntaglio, said coating having'its outer surface grained to retain moisture, applyin molsture to the said coating to be retaine thereby and in subsequently applying ink to the plate, said ink being retained by the printing surfaces and repelled by said coating.

18. The process of producing an intaglio plateA for printing by olf-set lithography, the steps which consist in graining a ieXible metal sheet, forming printing surfaces on said metallic sheet, applying a coa-ting to Asaid grained metallic sheet between the printing surfaces thereof, said coating being of a greater height than the printing surfaces to thereby render it intaglio, and having a grained surface substantially conforming to `that of the sheet to retain dampness and repel ink.

19. The process of producing an intaglio plate for printing by odset lithography,

the steps which consist in graining a flexible metallic sheet, producing photographic hardened portions of said substance from said sheet, applying a coating to the unexposed portions of said sheet, of a depth higher than the printing surface, to render it intaglio, said coating having its surfaces in grained formation to thereby render them hydrophilic to retain dampness, and 1n subsequently applying ink to said plate which adheres to the printing surfacesrand is repelledby the said raised coating. y

23. An intaglio plate for printing by offset litho raphy, said plate including ya grained sheet having photographic printing areas -thereon and a raised coating on said sheet between said photographie printing areas and higher than the same, said coating having its surface grained similarly to that ofthe sheet to thereby retain dampness and repel ink.

fn testimony whereof, l have hereunto si ed m name.

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printing surfaces on said sheet, applying a coating to said grained metallic sheet between the printing surfaces thereof, said coating being of a greater height than the printing surfaces to thereby render it intaglio, andv having a grained surface substantially conforming to that of the sheet to retain dampness and repel ink.

20. A method of producing .an intaglio plate for printing photolithographs, which method comprises coating a grained sheet of metal with a substance which hardens when ex osed to light, exposing said coating to lig t through a photographic negative, removing unhardened portions of said substance from said sheet and coating the unex-l posed portions of said sheet toa height greater than theexposed portion to render it intaglio. Y

21. rlhe method of producing an intaglio plate for photolithographs, which method comprises coating a Hexible sheet of metal.

with a substance which har-dens when exposed to light, exposing said coating to light through a photographic negative to thereby produce a printing surface, removing unhardened portions of said substance from said sheet, applying a coating to the unexposed portions of sald sheet, of a depth higher than the printing surface, to render it in'-,

taglio, said coating having its surfaces in grained formation to thereby render them hydrophilic to retain dampness.

22. The method of producing an inta lio plate for photolithographs, which met od comprises coating a flexible sheet of metal 4with a substance which hardens whenexposed to light, exposing said coating to light through a photographic negative to thereby produce a printing surface, removing unite 

